Please do not use ATF in your MTX. You WILL pay for it (literally) later on.
I think there was a post in this forum about it last week.
I respectfully disagree. ATF works well enough that it was factory fill for most of the life of the Contour with the change to Ford Honey just a few months before the end of production. Not only was it factory fill, Ford claimed that it good enough that it never needed changing.
Now, most anyone will tell you that there is no thing as lifetime fluid. Changing the ATF may have been enough to keep that from hapening. Also using a fluid with more friction modifier may have prevented those forks from getting so sticky. The additional friction modifier could be from adding Ford XL3 Friction Modifier as the Ford shop manual specified in 95 and 96 or it can be from a fluid that already has more friction modifier such at ATF+3.
Friction modifier makes the fluid more slippery. It is probably best that messing with the fluid formulation be left to oil chemists so a high quality fluid such as Torco, Specialty Formulations, or Royal Purple that is specifically blended for manual trans use would be preferred. Stay away from RedLine as we have seen that it isn't suitable due to sludging. RedLine should have been OK from it's published specs, but it wasn't.
The use of Mercon ATF, synthetic or dino, with added friction modifier has been well enough validated by many CEG members that it is safe. The use of ATF+3 has been as well.
Mercon by itself might not be too bad if changed often enough, but the overall shift quality and transmission operation is greatly improved by using a fluid that has more friction modifier than plain Mercon comes with.
Mercon V might also be a reasonable answer as it also has a bit more friction modifier than Mercon, but less than ATF+3.